1. Field of the Invention
This invention relates to a system and method for controlling the illumination of multiple LEDs.
2. Description of the Related Art
Developments in Light emitting diodes (“LEDs”) have resulted in devices that are brighter, more efficient and more reliable. LEDs are now being used in many different applications that were previously the realm of incandescent bulbs; some of these include displays, automobile taillights and traffic signals. As the efficiency of LEDs improve it is expected that they will be used in most lighting applications.
Different controllers have been developed to drive multiple light sources. U.S. Pat. No. 4,962,687 to Belliveau et al. discloses a variable color lighting system which includes light fixtures controlled from a central processor unit which includes a plurality of control channels. Each light fixture includes a plurality of chromatic light sources, and the intensity of each chromatic light source is controlled in accordance with a program from the central processor over the control channels. Each light fixture is assigned a channel address and responds only to digital input packet from the central controller that have the same address. The digital input packet controls how the light fixture changes color intensities.
U.S. Pat. No. 6,016,038 to Mueller et al. discloses a system with pulse width modulated current control for an LED lighting assembly, where each current-controlled unit is uniquely addressable and capable of receiving illumination color information on a computer lighting network. The invention can include a binary tree network configuration of lighting units (nodes) and can comprise a heat dissipating housing made out of a heat-conductive material, for housing the lighting assembly. The heat dissipating housing contains two stacked circuit boards holding respectively the power module and the light module. The light module is adapted to be conveniently interchanged with other light modules having programmable current and hence maximum light intensity, ratings.